R you covered?
Three months ago, the Department of Energy came out with new R-value recommendations for Southern Nevada. Do you know what that means? Should you be concerned? Well, your interest could save you more than a few dollars on your monthly energy bill.
R-value is the "resistance of heat transfer" found in home insulation. Every region of the country has a DOE-recommended minimum R-value rating. Las Vegas has an R-30 rating, while Minneapolis is R-50, according to Quinn Densley, division manager for Central Valley Insulation.
Densley said insulation is rated in terms of thermal resistance (R-value). This value indicates the resistance to heat flow; therefore, the higher the R-value, the greater the insulating effectiveness. Fiberglass (yellow, white, pink) and cellulose (gray) are the most common insulations found in attics and both are effective.
"The R-value of thermal insulation depends on the type of material, its thickness and its density," Densley explained. "There are homes here that have minimal insulation, because when we inspect them, we only measure 3 inches of insulation and that tells us the home was built with R-11 or R-15 minimal insulation. That's not enough. Determining how much insulation is in your home is vital to being energy efficient."
Densley said heating and cooling account for 50-70 percent of the energy used in the average American home. At the same time, inadequate insulation and air leakage are the leading causes of energy waste in the average America home.
"If installed properly, insulation should last for years and not lose its efficacy," he said. "The problem is that there isn't enough of it. So homeowners need to investigate and know that insulation saves money, it saves our nation's limited energy resources, and helps a home maintain a comfortable and uniform temperature by making walls, ceilings and floors warmer in the winter and cooler in the summer. I like to say that a house may be performing well, but that doesn't mean it's comfortable."
At Energy Sense, Robert Sprague said his company has partnered with Nevada Power to provide free energy inspections.
"We realize the importance of conserving energy," he said. "When we arrive at a home, our people check the water heater, furnace, look at insulation in the attic, and check duct work to determine if there are any leaks. The base inspection is free, although there could be some additional costs depending on how extensive the inspection is."
Sprague said local builders are in compliance with Energy Star standards set by the DOE. These standards are a government-backed, energy-efficiency program assisting businesses and individuals. He said anyone building a new home can ask for a higher R-value beyond what is recommended.
While adding additional insulation can by done by the homeowner, Densley said the job is dirty and it can be difficult getting all the necessary equipment into the attic.
"I'm not going to tell someone not to insulate themselves," he said, "but the job can be messy, you have to know how to navigate and crawl around an attic, have the proper hoses to blow the insulation, and, most important, (know) how much to use. There are some jobs that should just be left to the pros and I believe this is one of them."
HOW INSULATION WORKSHeat flows naturally from a warmer to a cooler space. In winter, the heat moves directly from all heated living spaces to the outdoors, adjacent unheated attics, garages, basements or wherever there is a difference in temperature. During the summer, heat moves from the outdoors to the house interior. To maintain comfort, the heat lost in winter must be replaced by your heating system and the heat gained in summer must be removed by your air conditioner. Insulating ceilings, walls and floors decreases the heating or cooling needed by providing an effective resistance to the flow of heat. Batts, blankets, loose fill and low-density foams, more familiarly called fiberglass, cellulose, polyicynene and expanded polystyrene, all work by limiting air movement. The still air is an effective insulator because it eliminates convection (air movement) and has low conduction. Blankets (batts and rolls) are mostly used for unfinished walls, including foundation walls, and floors and ceilings. They are best suited for standard stud and joist spacing and are good for do-it-yourselfers. Foam board or rigid foam is best for unfinished walls, including foundation walls, floors, ceilings and unvented low-slope roofs. It has high insulating value for relatively little thickness and can block thermal short circuits when installed continuously over frames or joists. Loose fill is recommended for enclosed existing walls, open new wall cavities, unfinished attic floors or hard-to-reach places. It is preferred when additional insulation is needed for existing finished areas, irregularly shaped areas and to fit around obstructions. Reflective insulation works by reducing the amount of energy that travels in the form of radiation. Some forms of reflective insulation also reduce air movement. By Jack Bulavsky
